> At the time Columbus crossed the Atlantic Ocean it was a (relatively) reasonable thing to do given the boat they had. Was it that reasonable at the time? Gra

> At the time Columbus crossed the Atlantic Ocean it was a (relatively) reasonable thing to do given the boat they had. Was it that reasonable at the time? Granted no one really thought they'd fall off the edge of the world and we did have long-time-at-sea experience, even if near the shore. Compared to today: the US has a decent track-record of landing on Mars. We have the tech to do it. We have a decent amount of experience in LEO. What makes a manned-Mars trip more or less absurd than Columbus' first trans-Atlantic voyage? Is it simply that Columbus hoped to be profitable by sailing to the East and we don't have that same expectation of a Mars mission?